1. Field of the Invention
The present invention relates in general to vehicles for transporting goods, and relates in particular to an integrated system for transporting and handling containers between aircraft and cargo terminals.
2. Technical Background
With increasing global trade, there is a trend towards increased use of containers at air terminals. The system for handling containers between an aircraft and cargo terminals has remained largely static for the past decade in spite of the increase in the number of containers being handled. Therefore, there has been a growing need to improve the efficiency of handling containers at air terminals.
For example, an existing system for handling containers at air terminals is described in a Japanese Patent Application, First Publication, S56-57532 (corresponding US priority application 82186, Oct. 5, 1979). The container handling system disclosed in this patent, illustrated in FIG. 6, includes a plurality of container dollys 2, each having a container 1 loaded thereon, being pulled by a small puller car 3. When the containers 1 are to be loaded onto the aircraft 4, a containers 1 loaded on a dolly 2 must first be transferred from the dollys 2 to the platform of a container loader 5 parked alongside the aircraft 4. The container 1 is then lifted by the loader 5 to the level of the cargo bay of the aircraft, and the container 1 is loaded into the cargo bay of the aircraft 4.
In the cargo handling system presented above, there are many deficiencies which affect the overall performance of the system. First, three operating components are involved in loading a container, and at least two operators are needed, one to operate the puller car 3, one to unload the container from the dolly 2 to the platform of the elevator 5, and possibly one more operator to operate the elevator 5. Next, it is necessary that after the completion of loading of the container from one dolly 2, each of the succeeding dollies 2 must be maneuvered into place for loading a next container. This type of handling system greatly reduces the operating efficiency of the entire container handling system. Further, the puller car 3 moves at a low speed of about 15 Km/hr thus limiting the overall handling capacity of the cargo handling system. An additional problem is caused by the potential for increased chances for a breakdown in two separate power sources needed for the system, i.e., container loader 5 having its own power source, the container dollys 2 which is powered by a puller car 3. Because these power sources are separate, a breakdown in one power source will make the entire system disfunctional, thus affecting the overall performance of the system.